Hydraulic hoisting apparatus



' H. 0. DAY

Nov. 15, 1938.

Filed July 6, 1956 Nov. 15, 1938. H. 0. DAY 2,137,045

HYDRAULIC HOI STING APPARATUS Nov. 15, 1938. H, 0, DAY 2,137,045

HYDRAULIC HOISTING' APPARATUS 5 Sheets-Sheet 3 Filed July 6, 1956 Patented Nov. 15, 1938 UNITED STATES PATENT OFFICE 2,137,045 HYDRAULIC HOISTING APPARATUS Herbert 0. Day, St. Paul, Minn, assignor to St. Paul Hydraulic Hoist 00., Minneapolis, Minn., a corporation of Michigan Application July 6, 1936, Serial No. 89,021 Claims. (01.298-22) This invention relates to hydraulic hoisting ap- This cross-head is pivotally connected to another paratus, wherein it is desirable to provide aconcorner of the triangular plate levers. To the struction for a hoist such as is used in hoisting other corner of the triangular plate levers I pivdump bodies of motor vehicles or the like to disotally connect a pair of built-up links which are 5 charge the contents thereof out of the dumping constructed to overlap and fold on either side of 5 body. It is desirable that the hydraulic hoisting the triangular plate levers along one edge thereof, apparatus b n tructed in a unit which may be while the outer ends of these links are connected mounted as such to the chassis of the motor veto a shaft to space them parallelly apart and to hicle upon which the hydraulic hoisting apparaconnect their outer ends with the frame upon tus is to operate. Further it is important that the which the dump body is mounted. 10 apparatus be so constructed as to compensate for The unitary construction of this lever and pisweaving and for the strain upon the respective ton connecting cross-head means provides a balparts so that the hydraulic hoist will operate anced lever structure parallelly operating and exunder complete control and with reliability when tending on either side of the piston so that the operated by the vehicle driver with the ordinary same can fold up into a compact state and can 15 knowledge of operating the vehicle and without e op ed to ho st a dumping body over the any essential information excepting the opera- 68mm o gravity into a high dumping position tion of the control valve means and clutch means without the necessity of restraining springs or for operating the fluid pump of the hydraulic Cables, yet providing a complete balancing of the hoist strain on the respective parts and a bracing 20 Hydraulic hoists on motor vehicles are subt ereof against uneven operation yet compensatjected to severe use and I have designed this unling for Weaving in the Operation of the motor tary hydraulic hoisting apparatus with compactvehicle. ness, strength, and a balanced lever means to The triangular plate levers, the cross-head,

withstand the strain and wear and tear to which and the links, are built up of sheet plate-like por- 25 the same is subjected, so as to provide efficient tions which are welded together to form an exoperation, as well as the necessary strength and ceptionally strong member. The triangular plate balance in the operating parts. levers have bearings formed in each corner there- A feature resides in providing ahydraulic hoistof, while the cross-head operates centrally bec apparatus wherein there are no multiplicity tween thetriangular plate levers and the links 30 of tubular passages for the hydraulic fluid which fold down onto the triangular plate levers into a can by vibration and strain break down and cause compact state. With plate levers and folding unnecessary leaks of the hydrau ic fiu connecting links of this character, together with Furth r, a feature resides in providing a frame the pivotal mounting of the piston, I provide a adapted to support the hydraulic hoisting unit hydraulic hoisting apparatus f ldable into a very 35 a reservoir Cross beam adapted t0 form he compact yet having a leverage means adaptbase and mounting for the hydraulic cylinder. ed to lift a dumping body into a greater angle e cylinder of the hoistmg apparatus is mount" with the center of gravity carried over the pived between the side members of the frame while otal mountin of the dum b d the reservoir supporting beam is pivotally secured body being gfuny f g g gg g gfig to said frame. This permits the whole cylinder assembly, including the strong substantial reser- Pushmned g h apparatus g any restram' voir base together with the pump and master mg P emg.necessary 0 the lever control valve to swing or pivot together in the and link CO IIDECtIODS and the cushioning action of +5 operation of the hoist in raising or lowering the the plston the .cyhnder of the hols/0' hoisting body. The unit includes a pair of tri- The drawmgs Illustrate the yd aulic hoisting angular shaped plate levers having a peculiar conapparatus m a' manner to Show f relatlve struction to provide a very strong and substantial opeljaung pPsitlon and f3n$tn1ct10n 0f the operating beam for carrying the heavy lo to Figure 1 1s a perspective of the unitary hoisting which they are subjected in raising the dumping apparatus with the levers in extended Position- 50 body. These triangular plate levers are pivotally Figure 5 n end V ew of the hoist when folded mounted at one corner of their triangular formainto Compact 100kihg toward the Outer end tion. Between the triangular plate levers I pro- 0f the piston rod and co c C oss-head.

vide a built-up cross-head which is adapted to be u e 3 is a en r ed de a l Of a portion of connected to the outer end of the piston rod. the hoisting apparatus, showing in dotted lines 55 the extended piston rod, cross-head, levers, and frame for supporting the dumping body.

Figure 4 is an edge view of the triangular plate lever.

Figure 5 is a detail section of one of the triangular plate levers on the line 55 of Figure 4.

Figure 6 is an edge view of one of the link levers.

Figure 7 is a section on the line 1-1 of Figure 6.

Figure 81s a plan view of the cross-head.

Figure 9 is a front edge view of the cross-head.

Figure 10 is a side view of the cross-head.

The lever and piston connecting cross-head means provides a construction as illustrated, wherein the hydraulic hoisting unit A includes ,a horizontally disposed cylinder B mounted be tween the parallel angular frame members ill to rotate on the shafts II which project from the reservoir beam 0, while the cylinder B is mounted on one side of the beam C. This provides a simple mounting for the cylinder B between the frame members ll so that the cylinder can pivot between these members freely and be folded therebetween, so to speak, with the lever and piston connecting cross-head means D.

The lever and piston connecting cross-head means D includes a pair of triangular shaped levers l2 which are mounted between the frame members ill, being carried upon the shaft l3 which is pivotally connected at l4 to the depending members I! forming a part of the frame members ID. The triangular lever plates i2 are connected to the cross-head member It by means of the shaft I! which extends through the bearing ll formed in the lever l2.

The pair of triangular levers l2 are adapted to be connected to a pair of links I! to pivotally connect at 23 one end of the links I! to the triangular levers l2. The pair of links I! are connected on The frame members 23 stringers or frame portions upon which the dump body (not illustrated) is secured or mounted. The frame members 23 are adapted to be supported by the rotatable bearing brackets 24 which are mounted upon the shaft 23 and supported at the rear of the frame members II.

The cylinder B is adapted to be centrally disthe shafts i i the cylinder is free to swing between the frame members i. while the triangular plate levers l2 are disposed in parallel relation to each other mounted upon the shaft IS in a manner to rotate parallelly with each other and equally spaced on each side of the cylinder B. Then with the cross-head connection It between the triangular plate members l2, it will be apparent that the plate members I! may be operated by the piston rod 23 through the connection of the cross-head I to operate the triangular plate levers l2 in the desired manner.

The triangular plate members l2 are built up of the side plates 21 which are parallelly disposed between the spacer plate members 23 which members are welded together to form an integral channel-like shape at the marginal edge of the levers l2 when the parts are integrally welded together. At each of the corners of the triangular plate levers l2, bearings such as ll, 23 and 33, are built into the triangular plate lever to form an integral construction with the plates 21 and the spacing plates 23. This provides a plate lever having a very strong construction, together with substantial bearings at the corners so as to form a lever connection with the piston wherein the connecting members may be held in line under heavy strain and load and to provide a lever and link connecting means with the operating hydraulic cylinder without any lost motion or back lash in the operation of the hydraulic hoisting apparatus.

The links I! are built up by the side plates 3| which extend parallel to each other and which are welded to the bearing sleeve 32 on one end and are held spaced apart by the plate web so that the side plates 3i extend parallel and are integrally connected to the web plate 33 and the bearing sleeve 32. The web plate 33 extends angularly from the bearing 32 toward one side of the side plates 3i, terminating at 34 at the edge of the plates 3! and spaced from the ends 35 which project beyond the end 34 of the web plate 33 to provide an the extremity of the ends formed with openings 36 which are adapted to receive shaft-like bolts to pivotally connect the links l9 at to one of the corner bearings of the triangular plate levers i2, as illustrated in Figure 1. It will be apparent that the links I 9 provide strong levers which are adapted to connect the triangular plate levers i2 through the shaft 2| to the frame 23 which supports the dumping body. Further, the links structed so that they will fold over the outside plates 21 of the triangular plate levers l2, as illustrated in Figure 3, which permits the folding of the levers and link means into a compact state on either sideof the forward end of the cylinder B and folding down between the sides of the frame III. This construction permits my underbody hydraulic hoist to fold down into a compact state with the working levers equally spaced on either side of the piston rod 26 and supported by strong bearings as well as providing lever and link means which have a substantial width to increase the bearing surfaces to hold the levers in line in operation.

I further provide a built up cross-head I which includes the centrally positioned shaft member I! which extends in a manner to project on either side of the top and bottom plates 31. The plates 31 are welded to the shaft l1 and I provide web plates 38 which extend between the plates 31 and which are welded to the plates 31 as well as to the shaft ll. The central portion of the shaft is formed square at 39 so as to provide a suitable flat bearing for the plates 31 and have a welding connection with the webs 33. The webs 33 are positioned on eitherside of the shaft to strengthen and space the plates 31 apart. When these parts are all welded together they form a very strong cross-head I i which is adapted to be connected to the piston rod 26 as illustrated in Figure 3. The cross-head l6 provides the central spacer between the bearings l3 of the plates l2 to hold the triangular lever plates i2 apart and brace the same in line with the bearings l4 on the ends of the shaft l3.

The piston of the cylinder B is operated by hydraulic pressure from the pump E which is driven by the shaft 43 which connects with the power plant of a motor vehicle in a suitable manner, not illustrated. The fluid pressure from the 35. The ends are open space from the point 34 to iii are conpump E is controlled by the master valve II which is provided with an operating lever 42 so as to set the valve in a manner to control the operation of the piston and connecting rod 26 to operate the triangular plate links l2 and the connecting link arms 19 to raise or lower a dumping body connected to the frame 23, the dumping body not being illustrated.

The unitary construction of my hoist with the triangular plate levers connected by the crosshead to the piston rod and to the member to be elevated into dumping position by the links i9, provides parallelly disposed lever and link means which extend in line, which are provided with wide bearing joints, and which fold together into a compact state or which are adapted to be extended to elevate the dumpingbody into a high angle without lost motion or back lash as the center of gravity of the dumping body is carried over the pivoting brackets which support the dumping body. The large triangular plate levers l2 brace the load as it is elevated against the tendency to twist or weave, while the cross-head braces these triangular plate levers centrally between the ends and causes an even pull to be exerted against the operating links l9. In the raising or lowering movement of the hoist A, the cylinder B pivots on the shafts H through the reservoir tank beam C which firmly holds the cylinder B in the frame I0, bracing the cylinder while its piston operates the connecting plate levers and link members through its connecting rod 26 and the cross-head It. The power of the cylinder B is carried through the plate levers and links equally balanced on each side of the cylinder B to uniformly distribute the load on the connecting cross-head IS without cramping the connecting rod 26 and with free pivotal movement through the same to the cylinder B even though the plate levers i2 and the connecting links l9 elevate the dumping body into virtually a perpendicular position if it is desired.

It will therefore be apparent that it is esential that the plate levers II, the connecting links l9, and the cross-head l6, operate to balance the load on either side of the piston and to operate in line through the bearings which connect the piston of the cylinder B with the load so that when the cylinder B is filled with hydraulic fluid, the piston may act without lost motion to cushion the load carried by the lever and link means which permits a high dumping angle of the load without undue strain upon the hydraulic hoisting unit A. The body which carries the load is also controlled so that it can be pulled down out of dumping position by the power of the hoisting mechanism A, being perfectly balanced in said hoisting mechanism and cushioned at all times by the hydraulic fluid in said hoisting unit.

I claim:

1. A hydraulic hoisting apparatus including a cylinder, piston and piston rod, a cross-head mounted on the outer end of said piston rod having shaft ends projecting from the side thereof,

triangular plate-like levers having bearings formed in each of the corners thereof, said crosshead being mounted in the bearings of one of the corners of said levers, a frame for pivotally supporting one end of said cylinder, means for pivotally supporting said triangular plate-like levers at one corner to said frame, links connected on one end to the remaining bearing in said triangular levers and having their outer ends pivotally connected to a member adapted to be elevated into dumping position, said links being mounted so as to straddle and fold onto said triangular levers substantially throughout their length in the folded and lower position of said hoist, and said triangular levers acting as a brace against lateral movement in the operation of the piston of said hoist to maintain the hoisting force in line in the operation of said hoist.

2. A hydraulic hoisting unit comprising a frame, a cylinder pivotally secured to said frame, a piston and piston rod on said cylinder, a cross-head on said piston rod, a pair of levers pivoted to said cross-head said levers being pivoted to said frame, a body to be hoisted pivotally secured to said frame, and links connecting said levers to said body, each of said links including a pair of spaced side members secured to straddle one of said levers through the greater part of its length,.,,and intermediate members connecting said side members and supporting them in definite spaced relationship.

3. A link and lever connection between a frame and a body pivoted thereto, including a lever pivoted to said frame and alink connecting said lever and said body, said link including spaced side plates mounted to straddle said lever at one end at all times, and means connecting said side plates, said last named means being positioned to permit said side plates to straddle said lever throughout a greater portion of its length when said link and lever are pivoted together.

A link and lever connection for a frame and body pivoted with relation to the frame including a lever pivoted to said frame and a link pivotally connecting said lever and said body, said link including a pair of spaced plates and means connecting said plates comprising a connecting web secured diagonally between said side plates to reinforce said plates throughout their entire width.

5. In combination with a frame member and a body member pivotally secured thereto a connecting means including a lever pivoted at one of said members, a link connecting said lever to the other of said members said link and lever mounted to provide slight relative angularity therebetween when said body is folded against said frame, said link including a pair of spaced plates straddling said lever and a connecting means supporting said plates in definite spaced relation and angularly disposed for engaging an edge of said lever when said body is folded against said frame.

HERBERT 0. DAY. 

